Rido Kuran is a pureblood vampire, Senri Shiki's father, elder brother to Haruka and Juri Kuran. Shizuka Hio was his fiancée. He is the main antagonist of the story. According to Asato Ichijo, he is the true head of the Kuran family. Ten years ago, seeking to take the Kuran princess, Yuki- Rido killed his brother, Haruka. Kaname attempted to kill Rido, but found he was unable to and a triumphant Rido revealed that as the one who revived Kaname, he is Kaname's master. Instead Kaname reduced Rido to the state where he required another pureblood vampire's blood in order to revive fully.

Secretly aided by the Ancient Vampire Council and the Hunters' Association, Rido manipulates events from the shadows by transferring his soul to other bodies and taking control. Rido possesses eyes of two different colors (crimson and blue), and when his soul is transferred to a different body, that body has eyes of two different colors. Rido's takes possession of his son's body and returns to Cross Academy. After a brief confrontation with Kaname and later Rima, Kaname gives his blood to Rido's body in order to restore Rido to his original body.

Ichiru reveals that Rido is the one who added Shizuka's ex-human lover to the list of Level E vampires to be liquidated by the Hunter's Association. Following his true body's revival, Rido's vampires sense his revival and begin to attack the school students, in order to capture prey for Rido to feed on. Ichiru attempts to kill Rido as revenge for Shizuka, but instead is mortally wounded by Rido. Rido attempts to compel Aido to feed upon him, but is thwarted by his niece. Seeing Yuki's resemblance to her mother, Rido changes his original desire from eating Yuki (in order to gain power) to instead taking Yuki as his lover as a replacement for Juri, who he loved but never wanted him. Rido's life comes to an end when he is defeated by Yuki and Zero.